Autogenous welded laminated expansion joint for conduits



April 29, 1958 ,AF, P, FARRAR ErAL i 2,832,613

AUTOGENOUS WELDED LAMINATED EXPANSION JOINT FOR CONDUITS Filed June l0.1954 3 Sheets-Sheet 1 April 29, 1958 J. F. P. FARRAR ETAL 2,832,513

AUToGENoUs WELDED LAMINATED EXPANSION JOINT FOR coNDUITs Filed June 10.1954 5 Sheets-Sheet 2 JNVENTORS.

April 29, 1958 J. F. P. FARRAR ETAL AUTOGENOUS WELDEDYLAMINATEDEXPANSION JOINT FOR CONDUITS 3 Sheets-Sheet 3 Filed June l0, 1954JNVENTORS' .f di() @y ,1%.

AUTOGENUS WELDED LAMINATED EXPAN- SION JONT FR CONDUTS John F. P,Farrar, Maywood, and David Wendell Fentress, Barrington, Ill., assignorsto Flexonics Corporation, a corporation of Illinois Application June 10,1954, Serial No. 435,695

6 Claims. (Cl. 285-226) This invention relates to expansion joints ofthe type adapted for insertion into pipe lines and other conduits forthe absorption of expansion, vibration, misalignment, and the like.

Expansion joints are employed in the pipe lines and other conduitconnections for the absorption of expansion, vibration, andmisalignment. Sizes commonly employed are from four inches to thirtyinches in inside diameter, although in some installations smaller andlarger sizes are employed.

Expansion joints Vare frequently called upon to absorb major degress ofmovement, in relation to their size or length, but ordinarily in suchcases the required rate of movement, or cycling of operation over anypredetermined period of time, is low.

ln the past expansion joints have commonly been constructed of a singlelayer of metal forming the tube wall. As the joint exes in service, forexample in an installation wherein the joint is called upon to absorbexpansion between conduits, each convolution of the joint may move asmuchas 1/2 of an inch or 3%: of an inch. Notwithstanding that therequired rate of movement may not be great, considerable bending andforces of stress result, often leading to premature rupture anddeterioration of the joint in service.

In accordance with the present invention the expansion joint is providedof a laminated wall construction, specitically a plurality of concentriclaminations, and means and methods are provided for the production ofsuch joints, in various required sizes, and for the suitable attachmentof end ttings thereto, in accordance with the requirements of variousservice and operating conditions.

lt is an object of the invention to provide an improved expansion joint,of improved operating characteristics.

More specifically stated, it is an object of the ine r kvention toprovide an improved expansion joint of laminated wall construction, andto provide improved means and methods for effecting the fabrication of astructure of this character.

Further objects of the invention are to provide an improved expansionjoint of the foregoing type which will be more durable in service, whichwill have increased flexibility in relation to its strength and pressurecapacities, which is more leakproof, and which is more adaptable tovarious conditions or" service and conducted iluid mediums with aminimum increase in cost.

A still further object of the invention is to provide, in an expansionjoint of the foregoing type, improved end connections and assemblies,and improved means and methods for effecting their fabrication.

Various other objects, advantages and features of the invention will beapparent from the following specification when taken in connection withthe accompanying drawings wherein certain preferred embodiments are setforth for purposes of illustration. This application is acontinuation-in-part of an application, Serial No. 795,-

O16, filed Dec. 3l, 1947, now abandoned.

nited States Patent() rifice In the drawings, wherein like referencenumerals refer to like parts throughout:

Fig. 1 is a perspective view, somewhat schematic in form, illustratingmeans and methods for effecting an initial step in the fabrication ofthe expansion joint of the present invention;

Fig. 1A is a detail view of a part of the apparatus shown in Fig. l;

Fig. 2 is a longitudinal sectional view of a further step in effectingthe fabrication of the joint body in aceordance with one preferredmethod;

Fig. 3 is an illustrative view showing the means of fabrication inaccordance with an alternate method;

Fig. 4 is a partial perspective view of the completed body, prior toeorrugation;

Figs. 5 vand 6 are illustrative views showing successive steps in thecorrugating of the body, to impart flexibility;

Fig. 7 is a longitudinal sectional view of the completed expansion jointbody, in accordance with the invention;

Figs. 8, 9 and 10 are views showing successive steps in the attachmentof end fittings to the body, in accordance with one embodiment;

Fig. 1l illustrates the application of rings to the structure forflexing control; f

Fig. l2 is a perspective view of the completed expansion joint, inaccordance with one embodiment; and

Figs. 13, 14 `and l5 are generally similar views, illustrating modifiedforms of structure and tting attachments.

Referring more specifically to the drawings, in Figs. l and 1A means andmethods are shown for effecting the fabrication of one laminated wallportion of the expansion joint body. As shown, a sheet 10, of the metalof which the joint is to be constructed, and of appropriate size, isfirst bent into generally cylindrical shape with its ends fitted intothe opposed slots 12 and 14 of an elongated fixture bar 16 havingsufficient length to align and position the sheet ends. The slots 12 and14 of the fixture bar are sufiiciently wider than the thickness of themetal sheet 10, so that free sliding movement of the sheetlongitudinally of the bar is permitted. As best shown in Fig. lA, thebar slots 12 and 14 overlap laterally, and are separated vertically onlya very slight distance so that the sheet ends 18 and 20 are superposedin substantially contacting relation when the sheet is in assembledposition.

The fixture bar 16 is suitably supported by means, not shown, injuxtaposition to a pair of welding rollers 22 and 24 forming a part of awelding machine, of suitable construction, and adapted for connectionwith the opposite ends of the welding transformer seconda-ry, asdiagrammatically indicated by the electrical connections shown. As thesheet 10 is shifted longitudinally of the fixture bar, to the right asseen in Fig. 1, the superposed sheet edges 18 and 20 will be broughtbetween the welding rollers, so that upon application of the weldingcurrent, a longitudinal seam resistance weld will be formed along thesheet edges so as to form the sheet 10 into a cylindrical-body member,as shown.

In accordance with the methods of fabrication illustrated in Fig. 2, anexpanding and Calibrating plug 26 is then drawn through the body member10 so as to expand it from its original cylindrical size, as indicatedYat 28, into a predetermined larger size as shown at 30. As will beunderstood, the body size 28 will be predetermined bythe original sizeof the metal sheet, due to the fact that the overlap of the sheet edges18 and 20 is accurately predetermined by the fixture bar 16. Accordinglythe body size 28 may thus be accurately predetermined by a properdetermination of the original sheet size of the body member.

The size 30 is determined by the cylindrical size of the expanding andcalibrating plug. This size is predetermined so that the body memberwill be ex` panded just suliiciently to permit the free insertion ofanother body member, as indicated at lila in Fig. 2, having a sizecorresponding to the original size of the body member 10, and fabricatedin a similar manner. The expanding and calibrating plug 26 may be drawnthrough the body 19, to elfect the expansion thereof, by suitable meanssuch as a cord or wire 32 connected to a power source.

After the assembly of the body 10a3within the body 10, so as to form alaminated wall structure of double lamination, the expanding andcalibrating plug 26 may be again drawn through the composite structure,and a further body member of the same original size again inserted, toprovide a triple wall lamination. ln this manner a laminated wallstructure of a desired number of laminations, within limits, may befabricated. It will be seen that each expanding operation expands thecylindrical bodies, one or more depending uponthe number assembled, thesame given distance; so that the same controlled degree of expansion iseffected by each operation of the expanding plug.

While the foregoing method of fabrication is suitable for expansionjoint bodies, in the smaller sizes, and having a smaller number oflaminations, for increased sizes and increased numbers of laminationsthe method of fabrication as indicated in Fig. 3 may be preferred. Inaccordance with this method the various sheets of which the body is tobe formed, as indicated in this instance as sheets 10a, 10b, lilo, 10dand 10e, are of progressively increased size, in accuratelypredetermined increments. As the sheets are successively formed intocylindrical body shape, in accordance with the methods illustrated inFig. l, each set of sheet edges having the same controlled degree ofoverlap, cylindrical bodies of successively increasing size will befabricated. Preferably the increasing size is such that each vbodymember may be just slipped into the next larger body member, whereby tobuild up a laminated body wall of the desired number of laminations. Thecompleted body, as fabricated either by the method of Figs. l and 2 orthe method of Figs. l and 3, is illustrated in Fig. 4. For uniformity ofoperation in service, the welded overlapped edges for each walllamination are preferably displaced uniformly as indicated at 34, 36,38, 40 and 42 in Fig. 4.

In accordance with the preferred methods herein disclosed, the multiplelaminated body is next corrugated for flexibility, by means and methodsas indicated in Figs. 5 and 6. The laminated wall structure, afterassembly and in composite form, is mounted between a pair of end plates44 and 46, and associated split clamps 48, Fig. 5, forming a part of ahydraulic corrugating machine. The machine further includes a pluralityof split die plates 50 initially mounted in uniformly spaced,predetermined xed position. Upon the introduction of liquid, underpressure, into the interior of the laminated body structure, by means ofthe conduit 52; coupled with the power propulsion of the plates 44 and46 toward each other by suitable means, such as piston rod S6, aprogressive corrugating of the body takes place as indicated at 54 inFigs. 5 and 6. During the corrugating operation the die plates 50 arereleased for free floating movement relatively toward each other whilebeing constrained from lateral separation. When the formation of thecorrugations 54 is completed, as shown in Fig. 6, the die plates 50 arebrought into abutting relation, and the body corrugations are formed toa pitch and contour as determined by the contours and size of the dieplates. The completed corrugated body, as thus fabricated, isillustrated in Fig. 7.

VMeans and methods for assembling end fittings onto the laminated body,in accordance with one embodiment, are illustrated in Figs. 8, 9 and lU.Expansion'joints,`

particularly in the larger sizes, are frequently interconnected withpipe lines'and conduits of Vruggedhea'v'y duty construction, and withinwhich large forces of expansion and vibration may be generated. Suchinstallations require heavy duty end fittings on the expansion joint,for interconnection with the conduits, so as to provide a rugged yetleakproof connection. The provision of a laminated wall expansion jointpresents the problem of securing a heavy duty end fitting to therelatively frangible and thin laminations of the body wall section.

As illustrated in Figs. 8-l2, the end fittings for the expansion jointcomprise a pair of relatively heavy duty iiange members and 62 of thetype adapted for cooperation with similarly formed fiange'members on theend of the connecting pipe conduits, the ange members being providedwith circumferentially spaced openings 64 for receiving the securingbolts.

As shown in Figs. 8-10, wherein the securingl of the flange" member 60is illustrated, it will be seen, Fig. 8, that such flange member isfirstv slipped over the extending neck portion 66 of the laminated body,away from the end thereof, after which an adapter collar as indicated at68 is inserted internally of the body end.V This adapter collar ispreformed, of suitable size and shape, and is of single wall thickness.

After insertion of `the`adapter, a circular seam resistance weldVbetween the adapter' and the body end is formed, as indicated at 70,Fig. 9, by means of a pair of welding rollers "l2 and 74 adapted tocooperatively grip the parts and 'to be shifted relativelycircumferentially thereof, as for example by suitably rotating'theexpander body between the welding rollers after the adapter member hasbeen applied. After the formation of the circular seam resistance weld,the fitting`60 is movedto operative position, as shown'in Fig. '10.

The circular weld 70 not only secures the adapter 68 into position, butalso welds the several'laminations of the expander body together in aHuid-tight joint, so that should one lamination become ruptured or leakin service, the leakage thus resulting will be localized to thedefective Wall lamination, and an effective fluid-tight seal maintainedby the remaining wall laminations of the expander body structure. Themass of the adapter 68 though greater than the 'mass of the individualbody laminations, is no so disproportionate as to preclude effectiveresistance seam. welding; and is considerably less than the mass of theflange member 60 which is proportioned to the stress requirements of theinstallation. The thickness of the adapted 68r is selected to assureeffective welding to the laminated body without damaging thelaminations. To this end the adapter should probably not be greater thanthree times the thickness of the laminated body but generally runsaround twice the thickness and may approximate the thickness of thelaminated body. Such thicknesses do not require the excessive heatingwhich would tend to damage the laminations. Assuming an individuallamination to have a thickness of approximately .020 inch, a three-plybody would approximate .060 inch in thickness. `With an adapter threetimes as thick as the composite body, that is, .180 inch, the adapterwould be approximately nine times as thick as an individual lamination.However, this ratio is still substantially less than that of the moremassive mounting element 60, and the conduit 88 of Fig. 14, referred tohereinafter. The adapter member, being preformed, avoids hammering andforming operations after application to the laminated body, so as topreclude danger of injury to the frangible laminated wall section ends.

As shown in Fig. 1l, split rings may be applied to the structure so asto insure controlled flexing of the laminated expander body, in service.As shown in Figs. l1 and' 12, these rings comprise a series ofintermediate rings 'lidisp'osed between the convolutions 54, and shapedto conform to the contours thereof; and a pair of end rings 78 shaped toconform-to vand sized-in accordance with the extending neck portions ofthe laminated expander body. Bolts, as indicated at 80, are provided forholding the rings in assembled position. By means of the rings thusprovided, a controlled flexing of the expansion joint or expander unitis insured, in that the rings preclude the undue collapsing movement ofany one convolution, in operation, to the exclusion of the others. Moreparticularly, as the expansion joint is collapsed, the iiange portionsof the rings are ultimately brought into abutting engagement to preventundue collapsing movement of any convolution. Such controlled liexingequalizes stresses applied to the convolutions and increases durabilityof the unit in service.

ln Fig. 13 an embodiment is illustrated, employing control rings aspreviously described, but wherein a different form of and connection forthe expander unit is provided. In this instance the preformed adaptermember 84, corresponding in function and purpose with the adapter member68 previously described, is circular seam resistance welded to theextending neck portion of the expander body, as indicated at 86; suchcircular seam resistance weld also acting to seal the severallaminations of the body wall together in a series of fluid-tight pocketsections between the laminations. The adapter member, being ofrelatively heavier Wall section than the individual body laminations,may be readily welded to the conduit end 88 by means of a circular weld90 which may be either an arc weld or a circular seam weld, as desired,and as may best be formed in accordance with the requirements of theparticular installation. The rings 76 and 78, for controlled exing, maybe applied to the unit after the welding operations, as in theembodiment of the invention previously described.

In Figs. 14 and 15 expansion joints are illustrated, correspondingrespectively with the joints of Figs. 1l and 13, with the rings forcontrolled ilexing not provided. The free flexing units of Figs. 14 and15 may in certain instances be desired.

The laminated wall expansion joint provided by the present inventiongives increased flexibility in relation to the strength and pressurecapacity of the expander; due

`to the fact that the strength and pressure capacity varies inaccordance with the composite wall thickness, whereas resistance toflexing varies substantially as the cube of the thickness of theindividual laminations multiplied by the number of laminations provided.IFurthermore, the degree of movement of the convolutions, in theinstance of a laminated wall, is considerably greater before astretching of any metal fibers beyond their elastic limit occurs; sothat a large degree of movement may be provided by the expander, butwithout stress of any of the metal libers of the laminated wall beyondtheir elastic limit. Longer life and greater durability in service isthus provided. The several wall laminations, being individually sealedat their ends, provide a multiple barrier for uid tightness.

In accordance with the invention, the various laminations of the bodywall are selected as to metal, in accordance with the lrequirements ofthe installation. For example, if a corrosive fluid is to be conducted,the innermost 4wall lamination will be selected of a metal resistant tothe corrosive action of the particular fluid involved. If dissipation ofheat is simultaneously a factor, the other body laminations are selectedwith a view toward conduction and radiation of heat from the unit. Inthis way the unit is adapted to the particular service requirements ofthe installation, with a minimum of over-all cost.

It is obvious that various changes may be made in the specificembodiments set forth without departing from the spirit of theinvention. The invention is |accordingly not to be limited to thespecific embodiments shown and described, but only as indicated in thefollowing claims.

We claim:

1. An expansion joint for connection in a conduit line for absorbingexpansion, contraction, vibration, misaligr' ment and the like therein;and comprising a yconvoluted expander body of a metallic laminated thinwall structure including laminate annular end portions, means forsecuring the end portions in the cond-uit line and including an adaptermember telescoped with an adjacent end portion of the expander body andannularly `welded thereto by a continuous autogenous weld located withinthe extremities of the telescoped surfaces between the end portion ofthe expander body and the adapter member and securing together theindividual wall laminations of the end portions of the expander body andthe telescoped portion of the adapter member, said adapter member'comprising an annulus having a thickness materially greater than thethickness of the individual wall laminations of the expander body andwithin the range of substantially the composite thickness of thelaminated wall structure of the end portion and a thicknessapproximating three times the Isaid composite thickness of the laminatedwall structure whereby to provide a ywelded joint between the endportion of the expander body and the telescoped adapter member forwithstanding stresses incident to movements of the expander body in theconduit. line while precluding dam-age to the wall laminations dur-- ingwelding, said adapter member having a portion thereor`v extendingoutwardly from the telescoped end of the expander body, and an annularend fitting more massive than said adapter member and cooperating withthe out-- wardly extending portion of the adapter member for supportingthe expander body in the conduit line.

2. An expansion joint as claimed in claim 1, wherein the end iittingcomprises a relatively massive annular mounting ring abutting theoutwardly extending portion of the adapter member, and wherein there areprovided intermediate reinforcing rings around the convolutions of theexpander body land an end reinforcing ring interposed between themounting ring and the adjacent intermediate reinforcing ring andsubstantially overlying the remaining portion of the end portion of theexpander body.

3. An expansion joint as claimed in claim 1, wherein the end tting isseparately welded to the outwardly extending portion of the adaptermember, Iand `wherein there are provided intermediate reinforcing ringsaround the convolutions of the expander body and an end reinforcing ringsubstantially overlying the end portion of the. expander body with theouter end thereof disposed adjacent the separate welded connectionbetween the adapter member and the end fitting.

4. An expansion joint 'as claimed in claim 1, wherein the adapter memberis preformed to include a substantially cylindrical portion telescopedwith the end portion.` of the expander body and a free end portiondisposed radially outwardly of the cylindrical portion and adapted.' forassociation with the end fitting.

5. An expansion joint as claimed in claim 1, wherein the end fittingembraces the end portion of the expande-rV body in the vicinity of thewelded connection between said end portion and the adapter member.

6. An expansion joint as claimed in claim 1, wherein the end fittingcomprises a yconduit member separately welded to the outwardly extendingportion of the adapter member.

References Cited in the file of this patent UNITED STATES PATENTS979,460 Fulton Dec. 27, 1910 1,505,121 Allport Aug. 19, 1924 1,797,151Lord Mar. 17, 1931 1,835,314 Lord Dec. 8, 1931 2,207,146 Fentress et al.July 9, 1940 2,263,714 Bloomfield et al Nov. 25, 1941 2,330,039 FeenstraSept. 21, 1943 2,337,038 Fentress Dec. 21, 1943- (Other references onfollowing page) UNITED STATES PATENTS A Kepler Dec. 21, Rosenblad May23, Fentress Tune 13, Fentress Dec. 19, Tobey et al. Jan. 28, SprengerMay 6,

Guarnascheli Jly 13,

